When protestors are arrested, it is most often for disorderly conduct. This “catch-all” category includes blocking traffic, harassing pedestrians, blocking entrance to a building, or making noise in residential area in the middle of the night. One form of disorderly conduct prohibited by Chicago ordinance is the failure to obey an order from police to “disperse,” or leave a particular area, in the vicinity of other people committing disorderly conduct. The ACLU believes that the First Amendment would be violated by the application of this ordinance provision to lawful demonstrators who failed to obey a dispersal order resting solely on the proximity of three law breakers, for example, where a crowd of lawful demonstrators contains a small number of persons who are throwing rocks at police or windows.